update genesis file content

[alexandratran]

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Make sure that:

• all commits in this PR are signed off for the DCO.
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Describe the change

Update genesis file content for clarity and consistency with GoQuorum docs (see Consensys/doc.goquorum#128).

Issue fixed

fixes #745

Impacted parts

For content changes

• Doc content
• Doc pages organisation

For tools changes

• CircleCI workflow
• Build and QA tools (lint, vale,…)
• MkDocs templates
• MkDocs configuration
• Python dependencies
• Node dependencies and JavaScript
• ReadTheDocs configuration
• GitHub integration

Testing

Screenshots / recording

[bgravenorst]

LGTM